The Electromagnetic Properties Analysis And Structural Design Of Thrust Magnetic Bearings

Magnetic suspended bearings is a non-contact supported device using electromagnetic force to achieve rotor suspended in space. It has some advantage, such as no friction, no lubrication, no oil pollution, low energy consumption, low noise and long life. It's particularly applied in a vacuum, ultra-quiet room, high-speed, and other special circumstances, with wide application potential. The magnetic thrust bearing is a device for axial support, composed of disk, electromagnets, controllers, power amplifier and sensors.This paper firstly introduces the working principle of the magnetic thrust bearing, derives electromagnetic force formula and deduces the largest bearing capacity and dynamic load with magnetic analytical method. Also it discusses how the parameters of the thrust bearing mechanical system and the control system affect the electromagnetic force.Then, the numerical analysis by using finite element method for magnetic field of the magnetic thrust bearing is presented. Magnetic field of different stator structures is analyzed. The three states, such as floating, equilibrium, and sloping are compared. The influence of the structure on electromagnetic force is studied. And the effect of bearing materials, as well as marginal on the strength of the magnetic induction is discussed.Finally, through summing up the magnetic bearing design theory and methods ,magnetic bearing design software is builded on the basis of the VB programming tools, AutoCAD drawing tools and Ansoft finite element analysis software. The designed system of the magnetic thrust bearings is established. The main idea is, firstly ,using VB for parametric design programming of magnetic thrust bearings, secondly, using VB to develop AutoCAD 2006 and drawing, thirdly, importing the", dxf" file into Ansoft to analyze the magnetic field. Then, the parametric design of the magnetic thrust bearing structure is realized.